Work or utility vehicles, such as tractors, skid steers, four wheelers, bulldozers, and the like, are often adapted to be used with various types of attachments. For example, loaders may be attached to the front of such equipment with arms and hydraulic controls that allow the loader to be raised and lowered, and also rolled forward and backward. Many different implements may be attached to the front of the work vehicles, thereby allowing an operator to accomplish various tasks via a single work vehicle.
Conventional front-end loaders include a pair of lifting arms or boom assemblies that include towers or rearward ends that pivotally attach to a tractor and lifting arms or forward ends that pivotally attach to an implement. A coupler may be used to connect various implements to the lifting arms. As such, the owner of a work vehicle may change the implement attached to the work vehicle in order to address the needs of a particular job. Exemplary implements found on conventional front-end loaders include buckets, clam shells, plows, fork lifts, bale spears, and the like.
Generally, the arms of the loader and the attached implement may be controlled by a hydraulic system. Hydraulic cylinders may be configured to operate front-end loaders and their attached implements. Hydraulic lines may extend along an exterior (or routed along the interior) of the front-end loaders for powering the hydraulic cylinders.
Known attachments, such as grapplers, are typically connected to a boom assembly through a complicated linkage. Further, multiple actuating cylinders are typically connected to known grapplers in order to move grappling jaws with respect to one another. For example, a first hydraulic cylinder is operatively attached to an upper jaw, while a second hydraulic cylinder is operatively attached to a lower jaw. The use of multiple actuating cylinders may add time and cost to a manufacturing process.
Further, known upper and lower grappling jaws are pivotally secured to each other at a fixed pivot axis that limits how wide the grappling jaws may be spread apart when the grappling assembly is in a fully-opened position as well as limits the distance between the lower grappling jaw and a pivot point at the end of a loader arm. The fixed pivot axis also limits an amount of grasping force that can be generated by the grappling jaws. As such, the grappling assembly is limited to handling structures that fit between the grappling jaws and structures that need less than a certain amount of grasping force to handle. However, the operator may need to handle, grab, or move an element that has a size that is too large to fit between the grappling jaws or that may need an amount of grasping force greater than an amount of force that the grappling jaws can generate. The individual may view the purchase of different and distinct grappling assemblies that are sized to handle different structures having different sizes to be expensive and wasteful. Further, the time of completing a task is lengthened when the operator detaches the grappling jaws and attach a different grappler that is sized to handle the larger element.